1. Field of the Invention
The present invention relates to a test socket used to electrically test integrated circuits (silicon die).
2. Description of Related Art
Integrated circuits are typically housed within a plastic or ceramic package that is soldered to a printed circuit board. The integrated circuit die is typically connected to the package by either bond wires, tape automated bonding (TAB), or C4 bumps. In C4/TAB packaging the integrated circuit (die) is bonded to the substrate or tape during package assembly.
The integrated circuit must be electrically tested before the package is assembled to a higher assembly. Packages are typically tested at a component level by placing the package into a test socket. Individual test contacts probe the package at the correct locations to test the assembled package. The integrated circuit generates heat during the test procedure. The heat must be removed to insure that the junction temperature of the integrated circuit does not exceed allowed maximum values. C4 and TAB packages are typically constructed from a material which have relatively poor coefficients of thermal conductivity. The high thermal impedance of these packages can be detrimental when testing an integrated circuit that produces a large amount of heat.
Additionally, these packages are typically placed into burn-in ovens to test the integrated circuit at elevated temperatures. The high thermal impedance of the packaging and the test socket create relatively high temperature differentials between the die and the oven. The high temperature differential lowers the accuracy of the test and limits the set point of the oven. It would be desirable to provide a test socket for an integrated circuit that is more thermally efficient than sockets of the prior art.